Elevator-door safety control



April 29, 1924. 1 492,09

P. 0. KEILHOLTZ ELEVATOR DOOR .SAFETY CONTROL Filed Dec. 7. 1921 WIN Patented Apr. 29, 1924.

warren stares IPIERRE O; KEILHOLTZ, OF BALTIIVIORE, IIIARYLAND.

ELEVATOR-DOOR $AFE'IY CONTROL.

Application filed December 7, 1921. Serial No. 520,589.

To all whom it may concern:

I Be it known that I, PIERRE O. KEILHOLTZ, a citizen of the United States of America, residing in the" city of BaltimorqState of Maryland, have invented certain new and useful Improvements in Elevator-Door Safety Controls, of which the following is a specification.

A large proportio-nof elevator accidents are due to attempts by passengers to enter or leave the elevator by opening the door which the attendent has failed to fully close and fasten or is attempting to close, and on the other hand, a considerable amount of inconvenience and annoyance results from the failure of the attendant to open the door to its full width, to provide for the free exit and entrance of passengers.

The object of the present inventionqis 2O referred to by providing means for automatically controlling the operation of the door as hereinafter described,

The device consists of a detent or wedging member shown in the form of a lever which has operative engagement with a lockingor wedging surface during both the closing and opening traverse of the door, checking and preventing any backward motion of the door, i. e., motion in the, opposite direction to that of the particular traverseptaking place until the predetermined traverse is completed. In other words, starting with the door in wide'open position and moving it toward closed position, the detent immediately becomes operative to prevent any backward motion of the door, or motionin the direction of opening until it has been completely closed, when the detent is thrown out of operative position; and when the door has been completely closed, and is started toward open position the detent is reversed and again becomes operative to prevent backward motion of the door toward closed position, so that it cannot be closed until it has been fully opened, or opened to the predetermined extents In the accompanying drawing, I have illustrated an elevator door to which my applied. I i

. In the drawing Figure 1 is an elevation of, the bottom portion of a double elevator door, closed,-showing the detent or checlrin to eliminate both the danger and annoyance invention in the preferred form has been its operative position, corresponding to the closed posit-ion of the door;

Figure 2 is a similar view, showing the door partially open, moving toward open position, the detent being in operative position corresponding to the opening traverse. This view also shows the door and detent in dotted lines in full open position of the door, the detent being inoperative;

Figure 3 shows the door partially closed, with the detent in the position which it would occupy if the door were moving toward closed position.

Figure 4 is a section at right angles of the plane of Figures 1, 2 and 3, the same being taken on the line 4.4, Figure 1;

Figure 5 is an elevation on a reduced scale of an elevator door equipped with thedetent of the invention and provided with the usual fastening device for holding the door closed.

Referring to the drawing by numerals, I have 'illustrated a sliding door 1 and stationary grating 2. The door is hung in the usual manner, as by the means of rollers 8 on track 4. The, door is also provided with any preferred type of catch, as shown this is in the form of a pawl 10, pivotally mounted on the door and engaging a notch 11,. in a pawl track, or guide 13, above the door. The pawl is released by the operator when he desires to open the door. In the form shown this is accomplished by means of a crank or eccentric 14, rotated by any suitable means, as a hand wheel or knob 15, the eccentric engaging an upright thrust rod 16, sliding in suitable bearings 17 and engaging-the pawl 10 from beneath.

. The detent or wedging members as illustrated, consists of a depending lever arm 20, pivoted near the bottom of the door, in any suitable manner, as by means of a stud 21, to swing freely therefrom. The action ofthe detent should be so free that its own weight will cause it to assume a depending position. Beneath the detent, extending the full length of the traverse, of both doors is a locking plate 22, to cooperate with the detent hereinafter described,-or the detent may,-if the sill is wide enough bear directly on thesillwln the drawing'22 may be either anordinary sill or a special plate referred to'herein or a locking plate. In other words the; function of this plate ma be servedby The locking plate or sill 22, or other correspondingmember, is discontinued or apertured at 24, directly beneath the position occupied by the check lever'20, when the door is closed. And it is also slotted or discontinued at 25', beneath the'p osition occupied by check lever 20, when the door is in Wide-open position, so thatthe 'lever' is free to hang vertically, or otherwise to; hang free, when the door i's open wide, or to the predetermined open position, and when it is closed. i l

l/Vhile-the position of slot25 had" been re ferred to asbeneath the catch in thewide open position of the doorthis slot'mayas a matter of fact, correspond'to thepos'itiou of the catch in any predetermined open po sition of the door to which it isjdesiredto compel the operator to open the door before closing it. I When the door occupies any position other than those in which the .wedging member, detent or lever 20 extends into oneof the slots 24 or 25, the said lever rest as to its lower end 26 upon the floor, locking plate or sill 22, or moreparticularly the surface 23 thereof, at an acute angle'with the vertical, approximately the angle of pose, the lever being deflected from the. vertical in the opposite direction to that' in' which the door has moved in withdrawing the locking lever from thef slot 24 or 25. which it last occupied. This angle is such that any effort to reverse the niotionof' the door or move it backward, from or at a point intermediate the ends of eithertraverse, 1. e., carrying the detent. wedging member or lever toward the slot from which it has just been removed, will cause the le preferably is flat, the end surfaceibeing at right angles to the center radius; ofthe? lever. .Vhen the deviceoper'ate s the friction between the lever 20"ahd surface and the inclination of the jlevertothe surface are; such as to prevent slipping of the lever and the tendency of the .leverisfto rotate about its lows d; 26; sees easies the door. I Assuming the; door t gb g i sition, as shown in- 1 thelever- 20,

26 in slot 24. Inthis position the door is locked by the usual automatic. locking device, *a form of which'is illustrated in F ig. 5, at 10, 11, &-c. When the operator releases the lock 10, 11 and opens the elevator door the lever 20 is by contact with the surface 23'immediately rotated through a slight are, contra-clocl wise to the right of the centerposition, see full lines Fig. 2. As the door is moved toward open position the le: ver 20 retains its angular position as aforesaid, in. which it is readytov resist by the wedging action described, any attempt to reverse the motion of'the door until the door reachesits predetermined open position, when the lockinglever 2O falls into the slot 25, and again assumes the vertical.

If now the door having been fully opened or opened to the predetermined position corresponding to slot 25, is moved toward closed position, the lever 20 assumes an angular position to the left of the vertical, its" wedging action being the same as that just described so that ifthere is an effort too'pen'the door after it has started, the closing traverse thus will be resisted by the wedging action of" the lever 20, so that the door cannot be moved toward open position until it has, been fully closed. when the lever 20 again assumes the vertical position extending into'sl-ot 2.6, andbecomesinoperative. The-usual locking device, 10, 11, becomes effective when the door is closed, preventing the opening'of the door until .it; is released from within by the operator,

It will thus be apparent that the oper ator, having so far closed the door, partially or to such an extent as; to prevent'entrance, the. door cannot be forced by'anyone from without desiring to enter, and the operator who desires to take on such passengers mustfirst close the door. then unlock it and open it. In this way; all chance of confusion at sults in accident to passengers attempting to force an entrance just as the door is closed, when the operator thinking that closing of the door has been effected, throws on. the power. The device also has the advantage that it compels the operator to open the door to a predetermined extent, before he. can close it, which tends to eliminate the practice which is frequent on the part of in; different operators of partially opening. the doors and compelling passengers to squeeze through an inadequate opening.

Broadly stated the invention comprises means for resisting and preventing reversal of the opening and closing motion. of an elevator door between the full open and full defied betw ny is te m ed P tions of the door, the Same messe ger w see er irs-m mber d'sin'g r looking surface which is preferam fiat, and

loo

a freely swinging wedging member or detent, the swinging end of which normally rests on the locking surface inclining the detent at a slight angle to its position of equilibrium when hanging free, one said member being carried by the door and the other on any stationary support adjacent the well, the locking surface being discontinned adjacent the ends of the traverse or at the bearing point of the swinging wedging member at the said predetermined positions of the door to release the swinging wedging member, permitting it to swing through the vertical providing for its reversal at each end of the traverse.

As already pointed out any effort tending to reverse the motion of the door between the ends of its traverse causes the detent or swinging wedging member to engage the wedging surface tending to rotate the swinging member through the vertical increasing the vertical distance between the pivot and the bearing or wedging surface wedging the door and looking it against reverse motion.

I have thus described a single embodiment of my invention, specifically and in detail in order that the nature and operation of same may be clearly understood, however, the specific terms herein are used descriptively rather than in a limiting sense, the scope of the invention being defined in the claims.

What I claim and desire to secure by Letters Patent is:

1. In combination with an elevator door, mounted to slide in the direction of the plane of the door, means for preventing reversal of the direction of the motion of the door intermediate the ends of the traverse consisting of a detent lever, pivotally mounted to swing freely, a hard inelastic flat locking surface engaged by the swinging end of the lever, causing the lever to be inclined backwardly as to direction of motion of the door providing for a wedging action of the lever in. engagement with the surface when any reverse tendency is imparted to the door, the locking surface being discontinued at points separated by the length of the traverse to provide for the reversal of the inclination of the lever at each end of the traverse.

2', In combination with an elevator door mounted to slide in the direction of the plane of the door, a detent lever, pivotally mounted on the door to swing freely relatively thereto, a stationary locking member parallel to the traverse of the door to be engaged by the swinging end of the lever causing the lever to be inclined slightly from of incline of the lever at each end of the traverse.

3. lhe combination with an elevator door of means for supporting the same, providing for an opening and closing traverse in the planeof the door and in a substantially horizontal direction, a check to prevent backward motion of the door, intermediate the ends of the traverse, the same consisting of a lever mounted on the door to swing freely thereon normally depending and a substantially flat locking surface cooperating therewith, on which locking surface the lower end of the lever drags, being thereby inclined slightly from the vertical, in a direction opposite to the direction of traverse, the lever serving to engage the locking surface and clamp the same whenever a tendency opposite to the direction of its traverse is imparted to the door at any point inter mediate the predetermined ends of its traverse, the locking surface being discontinued at each end of the path of the lever to permit the lever to swing and become oppo sitely inclined as the door reaches the end of its traverse and changes its direction of motion.

4. In combination with an elevator door, means for resisting and preventing reversal of the opening and closing motions of the door between the full open and full closed or between any predetermined positions of the door, the same consisting of two members, a locking surface and a. swinging wedging member, which normally rests on the locking surface'inclining the wedging member at a slight angle to its position of equilibrium, one said member being carried by the door, and the other by a stationary support adjacent the well, the locking surface being discontinued at the bearing points of the wedging member at the said predetermined positions of the door to release the wedging member, permitting it to swing through the point of equilibrium providing for its reversal at each end of the traverse.

Signed by me at Baltimore, Maryland,

this 29th day of November, 1921.

PIER-RED. KEILHOLTZ. Witnesses V JULIA B. RoBnvsoN, CARRIE M. REELY. 

